diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/ui/components/AvatarCropDialog.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/ui/components/AvatarCropDialog.kt
index 63136077..af4f9002 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/ui/components/AvatarCropDialog.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/ui/components/AvatarCropDialog.kt
@@ -2,6 +2,7 @@ package com.utun.chat.ui.components
 
 import android.graphics.Bitmap
 import android.net.Uri
+import android.view.WindowManager
 import androidx.compose.foundation.Canvas
 import androidx.compose.foundation.background
 import androidx.compose.foundation.gestures.detectTransformGestures
@@ -10,27 +11,35 @@ import androidx.compose.material3.*
 import androidx.compose.runtime.*
 import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clipToBounds
 import androidx.compose.ui.geometry.Offset
-import androidx.compose.ui.geometry.Size
+import androidx.compose.ui.geometry.Rect
+import androidx.compose.ui.graphics.ClipOp
 import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.Path
 import androidx.compose.ui.graphics.asImageBitmap
 import androidx.compose.ui.graphics.drawscope.Stroke
+import androidx.compose.ui.graphics.drawscope.clipPath
 import androidx.compose.ui.input.pointer.pointerInput
 import androidx.compose.ui.layout.onSizeChanged
+import androidx.compose.ui.layout.boundsInWindow
+import androidx.compose.ui.layout.onGloballyPositioned
 import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.platform.LocalView
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.IntOffset
 import androidx.compose.ui.unit.IntSize
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.window.Dialog
 import androidx.compose.ui.window.DialogProperties
+import androidx.compose.ui.window.DialogWindowProvider
 import com.utun.chat.R
 import com.utun.chat.data.*
 import kotlinx.coroutines.*
 import java.io.File
 import kotlin.math.roundToInt
 
-/** Фото перемещается под неподвижным квадратом. Подтверждение передаёт владение исходным файлом репозиторию. */
+/** Фото перемещается под круглой рамкой аватара. Подтверждение передаёт владение исходным файлом репозиторию. */
 @Composable
 fun AvatarCropDialog(uri: Uri, onCancel: () -> Unit, onConfirm: (File, AvatarCrop) -> Unit) {
     val context=LocalContext.current
@@ -57,6 +66,8 @@ fun AvatarCropDialog(uri: Uri, onCancel: () -> Unit, onConfirm: (File, AvatarCro
                 requireNotNull(PhotoUtil.decodeOriented(file.path,sample)) { "cannot decode editor image" } to IntSize(w,h)
             }
             source=copied; bitmap=image.first; dimensions=image.second
+            LogManager.addLog("INFO","Avatar","Editor loaded original=${dimensions.width}x${dimensions.height} " +
+                "preview=${image.first.width}x${image.first.height} mask=circle")
         } catch (e: Exception) {
             withContext(NonCancellable+Dispatchers.IO) {
                 copied?.let { if (!it.delete()) LogManager.addLog("WARN","Avatar","Cannot remove editor source=$it") }
@@ -71,7 +82,13 @@ fun AvatarCropDialog(uri: Uri, onCancel: () -> Unit, onConfirm: (File, AvatarCro
             if (!file.delete()) LogManager.addLog("WARN","Avatar","Cannot remove cancelled source=$file")
         } }
     }
-    Dialog(onDismissRequest=onCancel,properties=DialogProperties(usePlatformDefaultWidth=false)) {
+    Dialog(onDismissRequest=onCancel,properties=DialogProperties(decorFitsSystemWindows=false)) {
+        val window=(LocalView.current.parent as DialogWindowProvider).window
+        DisposableEffect(window) {
+            // Compose 1.6 с usePlatformDefaultWidth=false измеряет по дисплею, а не по доступной области окна.
+            window.setLayout(WindowManager.LayoutParams.MATCH_PARENT,WindowManager.LayoutParams.MATCH_PARENT)
+            onDispose { }
+        }
         Column(Modifier.fillMaxSize().background(MaterialTheme.colorScheme.surface).systemBarsPadding().padding(12.dp)) {
             Text(stringResource(R.string.avatar_crop_title),style=MaterialTheme.typography.titleLarge)
             Text(stringResource(R.string.avatar_crop_hint))
@@ -84,13 +101,19 @@ fun AvatarCropDialog(uri: Uri, onCancel: () -> Unit, onConfirm: (File, AvatarCro
             val mx=if (image==null) 0f else ((photoW*scale-side)/2).coerceAtLeast(0f)
             val my=if (image==null) 0f else ((photoH*scale-side)/2).coerceAtLeast(0f)
             val dx=ox.coerceIn(-mx,mx); val dy=oy.coerceIn(-my,my)
-            Canvas(Modifier.weight(1f).fillMaxWidth().onSizeChanged { bounds=it }
+            Canvas(Modifier.weight(1f).fillMaxWidth().clipToBounds().onSizeChanged {
+                bounds=it; LogManager.addLog("DEBUG","Avatar","Editor canvas=${it.width}x${it.height}")
+            }
                 .pointerInput(image,bounds) {
                     if (image!=null) detectTransformGestures { _,pan,factor,_ ->
                         val old=zoom; zoom=(zoom*factor).coerceIn(1f,16f)
                         val s=maxOf(side/photoW,side/photoH)*zoom
-                        ox=(ox*zoom/old+pan.x).coerceIn(-(photoW*s-side)/2,(photoW*s-side)/2)
-                        oy=(oy*zoom/old+pan.y).coerceIn(-(photoH*s-side)/2,(photoH*s-side)/2)
+                        // При минимальном масштабе погрешность Float может дать отрицательный предел.
+                        val limitX=((photoW*s-side)/2).coerceAtLeast(0f)
+                        val limitY=((photoH*s-side)/2).coerceAtLeast(0f)
+                        ox=(ox*zoom/old+pan.x).coerceIn(-limitX,limitX)
+                        oy=(oy*zoom/old+pan.y).coerceIn(-limitY,limitY)
+                        LogManager.addLog("DEBUG","Avatar","Editor transform zoom=$zoom limits=$limitX,$limitY offset=$ox,$oy")
                     }
                 }) {
                 drawRect(Color.Black)
@@ -99,17 +122,20 @@ fun AvatarCropDialog(uri: Uri, onCancel: () -> Unit, onConfirm: (File, AvatarCro
                         ((size.height-photoH*scale)/2+dy).roundToInt()),
                         dstSize=IntSize((photoW*scale).roundToInt(),(photoH*scale).roundToInt()))
                     val x=(size.width-side)/2; val y=(size.height-side)/2; val shade=Color.Black.copy(alpha=0.6f)
-                    drawRect(shade,size=Size(size.width,y)); drawRect(shade,Offset(0f,y+side),Size(size.width,y))
-                    drawRect(shade,Offset(0f,y),Size(x,side)); drawRect(shade,Offset(x+side,y),Size(x,side))
-                    drawRect(Color.White,Offset(x,y),Size(side,side),style=Stroke(2.dp.toPx()))
+                    val circle=Path().apply { addOval(Rect(x,y,x+side,y+side)) }
+                    clipPath(circle,clipOp=ClipOp.Difference) { drawRect(shade) }
+                    drawCircle(Color.White,radius=side/2,center=Offset(size.width/2,size.height/2),style=Stroke(2.dp.toPx()))
                 }
             }
-            Row(Modifier.fillMaxWidth(),horizontalArrangement=Arrangement.End) {
+            Row(Modifier.fillMaxWidth().onGloballyPositioned {
+                LogManager.addLog("DEBUG","Avatar","Editor actions bounds=${it.boundsInWindow()}")
+            },horizontalArrangement=Arrangement.End) {
                 TextButton(onClick=onCancel) { Text(stringResource(R.string.cancel)) }
-                TextButton(enabled=image!=null && source!=null && side>0,onClick={
+                Button(enabled=image!=null && source!=null && side>0,onClick={
                     val crop=AvatarCrop(((photoW*scale-side-2*dx)/(2*scale*photoW)).toDouble(),
                         ((photoH*scale-side-2*dy)/(2*scale*photoH)).toDouble(),
                         side.toDouble()/scale/photoW,side.toDouble()/scale/photoH)
+                    LogManager.addLog("INFO","Avatar","Editor confirmed crop=$crop zoom=$zoom")
                     handedOver=true; onConfirm(requireNotNull(source),crop)
                 }) { Text(stringResource(R.string.avatar_upload)) }
             }
diff --git a/tools/chatgui-android/app/src/main/res/values-ru/strings.xml b/tools/chatgui-android/app/src/main/res/values-ru/strings.xml
index 34648990..1248ffc2 100644
--- a/tools/chatgui-android/app/src/main/res/values-ru/strings.xml
+++ b/tools/chatgui-android/app/src/main/res/values-ru/strings.xml
@@ -361,6 +361,6 @@
     <string name="avatar_storage_server">Сервер хранения: %1$s</string>
     <string name="profile_avatar_saved">Аватар сохранён. Публикация в группы продолжается; недоступные серверы будут опрошены повторно.</string>
     <string name="avatar_crop_title">Выбор аватарки</string>
-    <string name="avatar_crop_hint">Перемещайте и масштабируйте фото, чтобы выбрать квадрат.</string>
+    <string name="avatar_crop_hint">Перемещайте и масштабируйте фото, чтобы вписать его в круг.</string>
     <string name="avatar_none">Нет аватарки</string>
 </resources>
diff --git a/tools/chatgui-android/app/src/main/res/values/strings.xml b/tools/chatgui-android/app/src/main/res/values/strings.xml
index bd469ebd..a8ed201d 100644
--- a/tools/chatgui-android/app/src/main/res/values/strings.xml
+++ b/tools/chatgui-android/app/src/main/res/values/strings.xml
@@ -359,6 +359,6 @@
     <string name="avatar_storage_server">Storage server: %1$s</string>
     <string name="profile_avatar_saved">Avatar saved. Publishing to groups; unavailable servers will be retried.</string>
     <string name="avatar_crop_title">Crop avatar</string>
-    <string name="avatar_crop_hint">Move and zoom the photo to choose a square.</string>
+    <string name="avatar_crop_hint">Move and zoom the photo to fit the circle.</string>
     <string name="avatar_none">No avatar</string>
 </resources>